Since their introduction, the number of services and features for cellular telephones has steadily increased. At first, these mobile devices operated on analog wireless networks that enabled voice communication and simple paging features. Later, digital wireless networks for cellular telephones were implemented to provide more advanced features for voice and data communication, such as encryption, caller identification and short message service (SMS) text messages. More recently, some cellular telephones enable the browsing of web pages on the Internet, tuning to radio stations, playing streamed content, or other on-line services.
The functionality of cellular telephones has continued to increase and incorporate many of the features originally provided for in handheld electronic devices such as personal digital assistants (PDAs). Relatively simple PDA features such as keeping a list of contacts, a calendar, appointments, and the like have been generally integrated into recent cellular telephone models. Also, more advanced features are becoming more widely available such as playing streamed content and broadcasts. In the past, providers of streamed content/broadcasts have not been able to differentiate advertisements for cellular telephone users versus other types of users. Typically, advertisements included with the streamed content/broadcasts were more generically directed to the demographics of a typical viewer, not the particular user viewing the playing of streamed content/broadcasts.